Hi BigCityFire,
Here are what I used to replace my fender bolts with..... M6x1.0 https://www.mcmaster.com/#95735a216/=1a6nhn3
and for those ones that snapped off in the threaded insert, I used these to replace all the threaded inserts..... https://www.mcmaster.com/#96887a319/=1a6ni0n
The guy that I got my truck from used some 5/16 sheet metal screws to hold the fender on because he broke 100% of the bolts that hold on the driver side fender.....
and apparently those screws were okay with him(me not so much)...